In the conventional power supply of a backlight module, the inverter control circuit containing two different PWM control units is used to adjust the luminant state of the backlight module. The first PWM controller thereof is a dimming regulator with a working frequency of about 120˜220 Hz and used to adjust the brightness of the backlight module. The second PWM controller thereof has a PWM signal generator and a logic circuit and has a working frequency of about 53 k˜75 k Hz and is used to adjust the working cycle of the backlight module.
Different PWM controllers require their respective manpower, time and costs in their design, stock and material preparation. Besides, the structures of the circuits are more complicated. Further, if two identical PWM controllers are mistakenly installed in a power supply, the electronic device will malfunction or be damaged. Furthermore, as the two different PWM controllers are non-interchangeable, the insufficiency of either one in material preparation will cause the delay of fabrication. Therefore, the design of using two different PWM controllers has become a problem of the manufacturers. An inverter control circuit, which is simple in design and is easily managed in material preparation, is thus desired by the field concerned.